1. Field of the Invention
The present invention relates to a torsional vibration damper for incorporation into the torque transmission path between two components or subassemblies, especially for a hydrodynamic coupling device.
2. Description of the Related Art
Such torsional vibration dampers are used, for example, in the torque transmission path between a clutch piston of a lockup clutch arrangement and a turbine wheel, but may also be used in clutch plates or multiple-mass flywheels. Helical springs are generally provided as the damper members to provide the necessary elasticity and can be subjected to the action of respective control regions or control edges of two components or subassemblies that can be twisted relative to one another about an axis of rotation. When torsional vibrations occur as a result of the interaction with the respective control edges, the helical compression springs, whose longitudinal axes extend approximately in the circumferential direction, can be compressed. The two components or subassemblies to be coupled to one another via such helical compression springs generally comprise, as one of the subassemblies, two cover disk members that are connected to one another in a manner fixed in rotation and at an axial distance apart, and as the other of the components or subassemblies a central disk member which engages between the two cover disk members. Such arrangements require a relatively large amount of structural space and, in addition, are subject to the problem that the helical springs, extending approximately in the circumferential direction, are displaced radially outward by centrifugal force in rotating operation and, in doing so, make frictional engagement with at least one of the components. This frequently results, at least at relatively high speeds of rotation, in a disadvantageous effect on damping performance.
It is an object of the present invention to provide a torsional vibration damper for incorporation into the torque transmission path between two components or subassemblies wherein, with simple construction and reduced structural space requirement, a vibration damping performance that can be little influenced by external influences can be provided.
According to the present invention, this object is achieved by a torsional vibration damper for incorporation into the torque transmission path between two components or subassemblies, especially for a hydrodynamic coupling device, comprising at least two disk-like damper members. Each damper member has a radially outward coupling region and a radially inward coupling region, and at least one deformation region extending between the radially outward coupling region and the radially inward coupling region and capable of elastic deformation at least in some areas to permit a relative circumferential movement between the radially outward coupling region and the radially inward coupling region.
In the torsional vibration damper according to the invention, then, the principle of compressible helical springs or the like is relinquished; instead, deformation regions extending from radially outward to radially inward and capable of deformation are used and introduce the necessary elasticity into the torque transmission path. As, moreover, at least two damper members having such deformation regions are used in the torsional vibration damper according to the invention it is possible, for example, by producing the damper members by stamping technology from sheet metal material, by appropriate selection of the number of damper members or of the material thereof to combine a desired damping performance with ease of manufacture.
For example, it is possible to provide that the at least one deformation region extends between the radially outward coupling region and the radially inward coupling region, at least in some areas, with a circumferential extension direction component. The at least one deformation region may extend spirally, at least in some areas, relative to an axis of rotation.
In order to be able to transmit higher torques without the potential risk of damaging the damper members, it is proposed that at least two deformation regions are provided for at least one damper member. A very strong coupling with the various components or subassemblies can be achieved in that, for at least one damper member, the radially outward coupling region and/or the radially inward coupling region is/are of substantially annular form.
In order to be able to transmit relatively high torques, or to be able to provide a comparatively high spring stiffness, it is proposed that, for all damper members the radially outward coupling region is provided for coupling to a first of the two components or subassemblies and the radially inward coupling region is provided for coupling to the second of the two components or subassemblies. This ultimately means that all damper members are connected in parallel with one another, so that the spring constant provided by their respective deformation regions cumulatively gives an overall spring constant.
Alternatively, it is possible to provide that, for at least one of the damper members, the radially outward coupling region and/or the radially inward coupling region is or are coupled or capable of being coupled to, respectively, a radially outward coupling region and a radially inward coupling region of at least one further damper member. This ultimately means that at least two damper members are connected in series relative to one another, which results in a significantly longer spring travel.
For this purpose the radially outward coupling region or the radially inward coupling region of a damper member can be coupled to a first of the two components or subassemblies, the radially outward coupling region or the radially inward coupling region of another damper member can be coupled to the second of the two components or subassemblies, and the respective other coupling regions of the one damper member and of the other damper member can be connected to one another. In this arrangement, the respective other coupling regions of the one damper member and of the other damper member can be substantially directly connected to one another. As an alternative, however, it is also possible for the respective other coupling regions of the one damper member and of the other damper member to be connected to one another via at least one further damper member.
In the torsional vibration damper according to the invention, at least two of the damper members can be formed from different material and/or produced with different material dimensions and/or provide different damping spring constants and/or are provided in mutually opposite installation positions.
It is also possible for the damper members to be arranged lying one upon the other.
In order to obtain the desired elasticity, the damper members can be formed from spring steel material.
A strong coupling between various of the damper members and the components or subassemblies to be coupled can be achieved in that at least those coupling regions which can be coupled to the first and the second components or subassemblies, respectively, have a toothing-like coupling formation.
The present invention also relates to a hydrodynamic coupling device, especially a hydrodynamic torque converter or fluid clutch wherein a torsional vibration damper according to the present invention is provided in the torque transmission path between a clutch member of a lockup clutch arrangement and a turbine wheel and/or in the torque transmission path between a turbine wheel shell and a turbine wheel hub.
Other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein.